Could not hibernate system or hibernate failing

Problem:
Could not hibernate system or hibernate failing

Error Message:
Windows - System Error
Insufficient system resources exist to complete the API

Solution :
This problem typically occurs when the computer uses 1 gigabyte (GB) or more of RAM.  Try hibernating after closing  unneccessary programs and reducing the RAM usage.
    (or)
This problem occurs because the Windows kernel power manager cannot obtain the memory resources that are required to prepare the computer to hibernate.
Refer
http://support.microsoft.com/kb/909095